Emulsifiable rust preventive concentrate



EMULSIFIABLE RUST PREVENTIVE CONCENTRATE Roy A. Westlund, Jr., Roselle, and Charles E. Paxton,

Jamesburg, N. J., assignors to Esso Research and Engineering Company, a corporation of Delaware Application February 2, 1956 Serial No. 562,920

5 Claims. (Cl. 106-14) No Drawing.

This invention relates to rust preventive compositions. Particularly, the invention relates to emulsifiable rust preventive concentrates which comprise a blend of an alkali metal salt of an oil-soluble sulfonic acid, a neutral degras, a coupling agent, and a balancing agent which comprises a mixture of an organic amine and water.

In the manufacture of highly machined precision metal parts, it is customary to apply a rust preventive composition between machining operations to prevent corrosion of the machine surfaces. The usual type of rust preventive used in this operation consists of a blend of a rust inhibitor and a petroleum solvent. The rust preventive film is ordinarily quite thin and is seldom removed from the machine parts between a sequence of operations. These ordinary rust preventive materials are quite often satisfactory with regard to corrosion inhibition but suffer from a number of other disadvantages. For example, the fumes which are given off by the petroleum solvent used are quite often objectionable to the machinist. This is particularly true in operations where the metal parts are washed in hot water to remove metal chips and traces of metal working compounds prior to the application of the rust preventive composition. In such uses, the machine parts are normally in the neighborhood of 180 F. when dipped in the rust preventive composition and the heat causes objectionable fuming of the solvent. In addition, the rust preventive compositions which are based on petroleum solvents are quite flammable and present a potential fire hazard.

To overcome these deficiencies, rust preventives have been developed by the prior art wherein the petroleum solvent is replaced by water. These water base preventives may be applied in the same manner as the conventional solvent types, such as by brushing, dipping, swabbing, or spraying. These Water base rust preventives have the advantages of being non-flammable and are not objectionable from the standpoint of fuming. Such products are, moreover, less expensive to use.

These water base rust preventives are often heated to speed the evaporation of water from the coated piece. Stability of the emulsion towards heat is therefore necessary for a satisfactory product. Emulsifiable rust preventives comprise hydrocarbon oils which contain the required rust preventives and emulsifiers. They may be emulsified with from 1 to parts of water prior to application.

In spite of the fact that these prior art water base rust preventives represent an advance over the petroleum solvent type, they still have been found to have several deficiencies. The oily film remaining on the coated piece tends to drain from the metal and leave portions of it exposed. The oily film is readily displaced by finger pressure and thus any parts which are handled after coating are liable to fingerprint corrosion.

It has now been found, and forms the object of this invention, that a rust preventive concentrate for use as an emulsifiable rust preventive which has none of the deficiencies noted above can be prepared from a mixture of a hydrocarbon oil, a petroleum sulfonate, degras, a coupling agent, and a balancing agent.

The components of the concentrate will be more spe-, cifically described below.

MINERAL OIL The mineral oil component of the rust preventive concentrate of this invention will have a viscosity at 100 F. Within the range of from about 60 to 3000 SUS. .Any conventionally refined mineral oil distillate may be used whether of naphthenic or paraflinic origin. Preferred mineral oils have a viscosity within a range of from to 500 SUS at F. Especially suitable are the base crudes.

SULFONATES The sulfonic acids operable for forming the sulfonates I useful in the instant invention may be those derived either from petroleum or from synthetic alkyl aromatics. The sulfonic acids are ordinarily obtained by treatment of a lubricating oil fraction or'an alkyl aromaticwith fuming sulfuric acid. Synthetic sulfonic acids may also 7 be used. For instance, polypropylbenzene sulfonic acids,

didodecyl toluene sulfonic acids, octadecyl naphthalene sulfonic acids, polypropyl naphthalene sulfonic acids, and thelike are operable. Operable acids have molecular weights within the range of from about 250 to 800 and an average mol. wt. within the range of from about 400 to 550. For the purposes of this invention, it is preferred to use sulfonic acids having an average molecular weight within the range of from about,420 to 500.

The oil-soluble sulfonates are used in this invention in the form of alkali metal soaps. For example, the sodium soaps, potassium soaps, and lithium soaps of sulfonic acids may be used. The preparation of these soaps is well described in the literature and forms no part of the inventive concept. 7

Preferred sulfonates for use in preparing the rust pre ventive concentrates of this invention are the alkali metal soaps of sulfonic acids derived from petroleum sources and having average molecular weights of from about 420 to 520. Sodium petroleum sulfonates are especially pre ferred.

DEGRAS Degras or wool grease, as it is commonly known, is obtained by the solvent washing of wool. The solvent is flashedoft from the wash residue and there remains a dark-colored material. This material, crude Wool grease, may be refined by any of the various techniques known to the art to any desired degree of purity. The degras operable in the concept of this invention is substantially completely neutral and has the following typical inspection's:

Free fatty acid (as oleic) percent a 0.30 Moistur i 0. 18 Ash 0.09

3. Melting point (ASTM D127) F" 115 Mineral acidity None Iodine value (Wijs) 51.0 Saponification No 98.0 Unworked penetration (ASTM D937) 141 Ppt. No. (ASTM D-91) 0.10

COUPLING AGENT The component of the rust preventive concentrates of this invention which serves to emulsity the rust preventive base is referred to in the art as a coupling agent.

The present inventive concept contemplates the use of a coupling agent which is selected from the group of glycol ethers and polyglycol ethers having from to 15 carbon atoms. It is particularly desirable to select a coupling agent that is essentially as volatile as water; thus both the Water present and the coupling agent present in the final composition will evaporate from the protective film upon drying to give a residual film which will not re-emulsify if Water should condense upon it. Among the glycol ethers which are operable in the concept of this invention are ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, ethylene glycol monobutyl ether, propylene glycol monoethyl ether, and the like. Especially preferred among the glycol ethers is ethylene glycol monobutyl ether which is available commercially under the trade name Butyl Cellosolve.

Among the polyglycol ethers operable in this invention may be mentioned diethylene glycol ethers such as the monomethyl ether, the monoethyl ether, the monophenyl ether, etc., the dipropylene glycol ethers, such as the monoethyl ethers and the like. Especially preferred among the polyglycol ethers is diethylene glycol monobutyl ether, commercially available under the trade name Butyl Carbitol.

BALANCING AGENT The component of the rust preventive concentrate of this invention which serves to stabilize the emulsions at both normal and elevated temperatures and to prevent separation is referred to as a balancingv agent. This balancing agent comprises a mixture of an organic amine base and water in certain definite relative proportions.

The organic amine base is preferably selected from the group consisting of organic amines having a plurality of hydroxyl groups and polyoxy amines prepared by reacting an alkylene oxide with fatty amines and diamines.

Especially preferred among the polyhydroxy amines is triethanol amine.

The polyalkylene oxide derivatives of the fatty amines are prepared by reacting from 1 to 10 mols of an alkylene oxide, preferably ethylene oxide, with one mole of a fatty amine or diamine containing from 12 to 24 carbon atoms. The preparation of these materials is well de scribed in the literature and forms no part of the inventive concept.

The amines used may be mono amines, such as tetradecylarnine, hexadecylamine, octodecylamine and the like, as well as mixtures of these mono amines, or diamines such as N-dodecyl ethylene diamine, N-octodecyl ethylene diamine, N-tetradecyl ethylene diamine, N-tetradecyl propylene diamine, N-octodecyl propylene diamine, and the like, and mixtures of these diamines. Although the alkylene oxide is preferably ethylene oxide, other alkylene oxides, such as propylene oxide, butylene oxide, or mixtures of these may be used.

Especially preferred among the polyalkylene oxide derivatives of fatty amines or diamines is the poly- 4 ethylene oxide derivative of N-tetradecylpropylene diamine containing about five ethylene oxide units.

The ratio of water to the organic amine in the balancing agent is critical. If a balancing agent is prepared from a polyhydroxy amine, such as triethanol amine, the ratio of water to the amine should be between 4/1 and 14/ 1. If a polyalkylene oxide derivative of an organic amine is used, the ratio should be between 1/1 and 14/1.

To obtain an emulsifiable rust concentrate having the characteristics especially preferred, it is necessary to control the proportions of the ingredients used within narrow ranges.

The base composition of the mineral oil, the metallic sulfonate and the degras will comprise from about 72-95 wt. percent of the total formulation with a preferred range of from 77-94 wt. percent. The coupling agent comprises from about 1-l0 wt. percent with from 2-8 wt. percent being preferred. The balancing agent will comprise about 1-18 wt. percent of the composition with from 2-15 wt. percent preferred. The table below sets out the operable and preferred ranges:

Ranges (Wt. Percent) Operable Preferred Base Composition 72.0-95.0 77. 0414.0 Mineral Oil 10. 0-25. 0 15. 0-23. 0 Metallic Sulfonate 10.0-25.0 15.0-23.0 Degras 20. O-50. 0 35. 045. 0 Coupling Agent 1. 010. 0 2. 0- 8.0 Balancing Agent:

Polyhydroxy amine (H8. 0 3. (H5. 0 (Water/amine ratio) 4/1-14/1 7/1 Polyoxyalkyleneamine derivative 1. 0-18. 0 2. (H5. 0 (Water/amine ratio) 1/1-14/1 4/1 rust preventive tests which are known to the art.

The emulsibility test is conducted as follows: Twenty milliliters of the composition are added to eighty ml. of water at room temperature (77:5 F.) in a ml. graduated cylinder fitted with a ground glass stopper. The cylinder is inverted once and brought back to its original position. It is then shaken vigorously twenty times. Each shake is considered as one downward (or upward) motion of the hand and the return to the original position and each motion of the hand covers not less than one foot or more than two feet. This shaking should take from 10 to 15 seconds. The contents are examined for completeness of emulsification and if needed an additional 20 or 40 shakes are given as described. If at the end of 60 shakes the emulsion is not complete the emulsibility is rated poor. Complete emulsibility in 20 to 40 shakes is fair while a good rating in emulsibility denotes complete emulsification after 20 shakes.

In addition to the emulsibility test, the emulsion stability test was run. This test was conducted as follows:

A total of 100 ml. of water and the composition (at various water/composition ratios) were placed in a 100 ml. graduated cylinder as in the previous test. The mixture was shaken as previously described for 60 shakes without stopping. The graduated cylinder was then stored at 77 F. or F. for a period of 24 hours. At the end of this time the amount and type of separation was noted.

Table l EMULSIFIABLE RUST PREVENTIVES Composition (Wt. Percent) Blend N o 1 2 3 4 5 6 7 8 9 10 11 12 Base Blend 1 100. 0 90. 0 80. 0 95. 0 93.0 94.0 94. 0 93. 0 80.0 80. 0 80. 0 80. 0 Coupling Agent: Di-ethylene Glycol monobutyl ether 10. 0 20.0 5. 0 5. 0 5. 0 5. 0 5. 0 5. 0 5. 0 5. 0 5. 0 Ethylene Glycol monobutyl ether. Balancing Agent:

Triethanolamine 1. 0 1. 0 3. 0 1. 9 1. 3 Polyoxyethylene 010-13 Amine Product 1. 0 Polyoxyethylene N -Amino propyl octadecyl Amine Product Water 1.0 1.0 1.0 12.0 13. 1 13. 7 15.0 Water/Ammo Ratio 0 0 0 0 1/1 on 0 1/1 4/1 6. 9/1 10. 5/1 TestEReslfltlsil t 2 mu s1 i y poor fair oor 00d good good ood ood ood 00d 00d 00d Emulsion Stability Test (Percent Sepap g g g g g g g rated in 24 hrs.)-

Room Temp 30+ 30+ 2 2 2 2 2 2 2 2 2 160 35 2 43 30 30 7 4 2 20 Composition (Wt. Percent) Blend N o 13 14 15 16 17 18 19 20 21 22 23 Base Blend 1 80. 0 75. 0 70. 0 80.0 94. 0 90. 0 90. 0 80. 0 90.0 80. 0 80.0 Coupling Agent:

Di-ethylene Glycol monobutyl ether 5.0 10.0 10 0 5.0 5 0 5 0 5 0 5.0 5 0 Ethylene Glycol monobutyl ether 5 0 5.0 Balancing Agent:

Triethannlamine Polyoxyethylene 010-18 Amine Product Polyoxyethylene N-Amino propyl octadecyl Amine Product Water. Water/Amme Ratio 14/1 14/1 19/1 14/1 1/1 4/1 TestEResililtlsiz1 t 2 mu si i y good good good good ood good good good ood ood ood Emulsion Stability Test (Percent Separated in 24 g g g g 1 25.0 wt percent sodium petroleum sulfonate (460 av. mol. wt.) 50.0 wt. percent neutral degras25.0 wt. percent mineral oil (100 BUS/100 F.). Emulsion Rat1o: water/concentrate; 4/1-excepting Nos. 12-16 which were 3/1.

A careful examination of the data of Table I above will show the critical features of the concept of the invention.

Blend N0. 1 shows that the emulsibility characteristics of the base blend are unsatisfactory. Blends 2-4 indicate that varying amounts of the coupling agent can improve the emulsibility but do not improve the high temperature (160 F.) stability. Blends 5 and 6 show that 2.0 wt. percent of the balancing agent with a water/ amine ratio of 1/1 is an excellent product and that omission of the amine results in high temperature separation.

Blends 7-11 and 13-15 are directed to the polyhydroxy amine. A comparison of the data of Blends 7-11 shows that water is a necessary component of the balancing agent and that a water/amine ratio of at least 4/1 is required for good high temperature stability. Blends 13-15 show that the upper limit of the amount of coupling agent is about 10.0 wt. percent, preferably about 8.0 wt. percent.

Blend 12 shows that even 15.0 wt. percent water in the formulation without the organic amine results in an unsatisfactory product of unsatisfactory high temperature emulsion stability.

Blends 17-21 are directed to the polyoxy alkylene derivative of a C1048 fatty amine (the reaction product of a mixture of C -C amines with 5 units of ethylene oxide) and indicate that a water/amine ratio in the balancing agent of from 1/1 to 14/1 is operable. Blend 16 illustrates the operability of another species of a polyoxyalkylene derivative of an amine.

Blends 22 and 23 are directed to the species of a glycol ether and indicate that excellent results are obtained with this coupling agent.

Blends Nos. 5 and 13 from Table I were subjected to additional emulsion stability tests using water of different degrees of hardness.

Complete data on these tests are set out in Table II below. In addition, the standard JAN-H-792 Humidity 75' Cabinet Life was run on these reventives. These data also appear in the table below.

Table II EMULSIFIABLE RUST PREVENTIVES Blend No 5 l3 Composition, Wt. Percent:

Base Blend A 93.0 80. 0 Diethylene Glycol Monobutyl ether 5. 0 5. 0 Polyoxyethylene derivative of 010-18 fatty amine... 1. 0 Triethanol amine 1. 0 Water 1. 0 14.0 Water/amine ratio 1/1 14/1 Emulsion Ratio, Water/comp 4/1 3/1 Test Results:

Emulsibility Good Good Erlriulsign Stability Test (percent Separated in 24 ours 77 F., Tap Water 2 2 160 F., Tap Water 2 2 Water Hardness, p. p. in. Ca

2 2 ann 2 600.. 5 F

.0 2 150. 2 300.-. 2 600.. 10 JAN-H492 Humidity Cabinet Life: Hours 2 600+ 600+ 1 See Table I. 2 Panels dipped in emulsion 160 F., hung in laboratory for 16 hours, and placed in cabinet.

To summarize briefly, the instant invention relates to rust preventive compositions and particularly to emulsifiable rust preventive concentrates. The materials of this invention comprise a base material, a coupling agent and a balancing agent.

The base material which is present in amounts between about 72.0 to 95.0 wt. percent, preferably 77.0 to 94.0 wt. percent, consists essentially of from about 10.0 to about 25.0 wt. percent, preferably 15.0 to 23.0 wt.

percent, of a mineral oil having a viscosity at 100 F. of

" having from 10 to 18 carbon atoms and water, said last about 90 to 500 SUS, about 10.0 wt. percent to 25.0 wt.

percent, preferably 15.0 wt. percent to 23.0 wt. percent of an alkali metal salt of a sulfonic acid having an average molecular weight of from about 420 to 500, preferably a sodium salt of a petroleum sulfonic acid, and about 20.0 to about 50.0 wt. percent, preferably 35.0 to 45.0 wt. percent of a neutral degras;

mentioned mixture having a water/amine ratio of about H 1/1 to 14/1, said percentages being based on the weight The coupling agent is selected from the group consisting of glycol ethers and polyglycol ethers having from about 5 to 15 carbon atoms, and is present in amounts between about 1 and wt. percent, preferably 2 to 8 wt. percent. Especially preferred is diethylene glycol monobutyl ether.

The balancing agent comprises a mixture of an organic amine and water within a definite critical ratio. The organic amine is selected from the group of polyhydroxy amines and polyalkylene oxide derivatives of, a fatty amine having from 10 to 18 carbon atoms. If a polyhydroxy amine/water mixture is chosen as the balancing agent, it should comprise from 1 to 18 wt. percent, preferably 3 to wt. percent, of the composition andmust have a water/ amine ratio varying between 4/ 1 and 14/ 1. If a polyoxyalkylene derivative-water mixture is chosen as the balancing agent, it will be present in amounts between about 1 and about 18 wt. percent, with 2 to 15 wt. percent preferably, and the water/amine ratio is between the ranges of 1/1 to 14/1.

A specific preferred concentrate has the following com- What is claimed is:

1. An emulsifiable rust preventive composition that forms a stable emulsion when admixed with 1 to 10 parts of water, consisting essentially of from 72.0 to 95.0 wt; percent of a base material, from 1.0 to 10.0 wt. percent of a coupling agent, and from 1.0 to 18.0 wt. percent of a balancing agent, said base material consisting essentially of from about 10.0 to 25.0 Wt. percent of a mineral oil having a viscosity at 100 F. of about 90 to about 500 SUS, about 10.0 to 25.0 Wt. percent of an alkali metal salt of a sulfonic acid having an average molecular weight of from about 420 to about 500 and about 20.0 to about 50.0 wt. percent of a neutral degras, said coupling agent being selected from the group consisting of glycol ethers and polyglycol ethers having from about 5 to 15 carbon atoms and said balancing agent being selected from the group consisting of a mixture of a polyhydroxy amine and water having a water/ amine ratio within the range of from 4/1 to 14/1 and a mixture of a polyalkylene derivative of a fatty amine of the total composition.

2. An emulsifiable rust preventive concentrate that forms a stable emulsion when admixed with 1 to 10 parts of water, consisting essentially of from about 77.0 to

about 94.0 wt. percent of a base material, about 2.0 to about 8.0 wt. percent of a coupling agent and about 3.0 to about 15.0 wt. percent of a balancing agent, said base material consisting essentially of about 15.0 to about 23.0 Wt. percent of a mineral oil having a viscosity at 100 F. of about to 500 SUS, about 15.0 wt. percent to about 23.0 wt. percent of a sodium salt of a petroleum sulfonic acid having an average molecular weight of from about 420 to 500 and about 35.0 to about 45.0 wt. percent of a neutral degras, said coupling agent being se lected from the group consisting of glycol ethers and polyglycol ethers having from about 5 to 15 carbon atoms and said balancing agent being selected from the group consisting of a mixture of a polyhydroxy amine and water having a water/ amine ratio within the range of from 4/1 to 14/1 and a mixture of a polyalkylene derivative of a fatty amine having from 10 to 18 carbon atoms and water, said last mentioned mixture having a water/ amine ratio of about 1/1 to 14/1, said percentages being based on the weight of the total composition.

3. A rust preventive concentration according to claim 2 wherein said mineral oil has a viscosity at F. of about 90 to 500 SUS, wherein said coupling agent is ethylene glycol monobutyl ether, and wherein said balancing agent is a mixture of triethanol amine and water having a water/amine ratio of between 4/1 and 14/ 1.

4. A rust preventive concentrate according to claim 2 wherein said coupling agent is diethylene glycol monobutyl ether and wherein said balancing agent is a mixture of polyethylene oxide-C to C fatty amine condensate containing about 5 ethylene oxide units and water, the water/amine ratio being between 1/1 and 14/ 1.

5. An emulsifiable rust preventive concentrate that forms a stable emulsion when admixed with 1 to 10 parts of water, consisting essentially of about 20.0 wt. percent of a mineral oil having a viscosity at 100 F. of about 100 SUS, about 20.0 wt. percent of a sodium salt of a petroleum sulfonic acid having an average molecular weight of about 460, about 40.0 wt. percent of a neutral degras, about 5.0 wt. percent of diethylene glycol monobutyl ether, about 1.0 wt. percent of triethanol amine, and about 14.0 wt. percent of water.

References Cited in the file of this patent UNITED STATES PATENTS 2,182,992 Lebo Dec. 12, 1939 2,392,102 Ruedrich Ian. 1, 1946 2,408,971 Duncan Oct. 8, 1946 FOREIGN PATENTS 573,623 Great Britain Nov. 29, 1945 663,172 Great Britain Dec. 19, 1951 

1. AN EMULSIFIABLE RUST PREVENTIVE COMPOSITION THAT FORMS A STABLE EMULSION WHEN ADMIXED WITH 1 TO 10 PARTS OF WATER, CONSISTING ESSENTIALLY OF FROM 72.0 TO 95.0 WT. PERCENT OF A BASE MATERIAL, FROM 1.0 TO 10.0 WT. PERCENT OF A COUPLING AGENT, AND FROM 1.0 TO 18.0 WT. PERCENT OF A BALANCING AGENT, SAID BASE MATERIAL CONSISING ESSENTIALLY OF FROM ABOUT 10.0 TO 25.0 WT. PERCENT OF A MINERAL OIL HAVING A VISCOSITY OF 100*F. OF ABOUT 90 TO ABOUT 500 SUS, ABOUT 10.0 TO 25.0 WT. PERCENT OF AN ALKALI METAL SALT OF A SULFONIC ACID HAVING AN AVERAGE MOLECULAR WEIGHT OF FROM ABOUT 420 TO ABOUT 500 AND ABOUT 20.0 TO ABOUT 50.0 WT. PERCENT OF A NEUTRAL DEGRAS, SAID COUPLING AGENT BEING SELECTED FROM THE GROUP CONSISTING OF GLYCOL ETHERS AND POLYGLYCOL ETHERS HAVING FROM ABOUT 5 TO 15 CARBON ATOMS AND SAID BALANCING AGENT BEING SELECTED FROM THE GROUP CONSISTING OF A MIXTURE OF A POLYHDROXY AMINE AND WATER HAVING A WATER/AMINE RATIO WITHIN THE RANGE OF FROM 4/1 TO 14/1 AND A MIXTURE OF A POLYHYDROXY DERIVATIVE OF A FATTY AMINE HAVING FROM 10 TO 18 CARBON ATOMS AND WATER, SAID LAST MENTIONED MIXTURE HAVING A WATER/AMINE RATIO OF ABOUT 1/1 TO 14/1, SAID PERCENTAGES BEING BASED ON THE WEIGHT OF THE TOTAL COMPOSITION. 